I understand that Call ducks are very difficult to hatch(especially from shipped eggs), but could anyone explain why? I hatched out a singleton from 17 shipped eggs which, apparently isn't an uncommon hatch rate for them. I have tried to be VERY vigilant when incubating them, but apparently that isn't enough. Can anyone give me any tips? I have 14 more coming and these Call eggs AIN'T cheap! Thanks for any help.